A vehicle control device including a first calculation processing portion and a second calculation processing portion is conventionally well known. For example, this corresponds to a vehicle computer system disclosed in Patent Document 1. In the vehicle computer system of Patent Document 1, the first calculation processing portion and the second calculation processing portion have the same configuration and execute the same calculation process. The vehicle computer system compares certain data of the first calculation processing portion and the second calculation processing portion in a calculation process step with each other to detect an abnormality.